Hot Oxygen Corona at Mars and Its Effect on Solar Wind Deceleration

Phobos 2 plasma measurements have revealed solar wind deceleration of about 100km/s upstream of the Martian bow shock. It is suggested that the deceleration is due to the mass loading by the ions originating from the hot oxygen corona of Mars. In this study, we use a gas-dynamic model to estimate the solar wind deceleration caused by the mass loading effect and the result shows that the deceleration is only about 10--15km/s when we invoke the well established hot oxygen corona density profiles.